1. Field of the Invention
The invention relates to oral care compositions comprising diglycerols which unexpectedly have an enhanced and/or prolonged smooth lasting effect such as long lasting flavor and cooling characteristics in the mouth. The diglycerol provides humectant and emollient properties to the compositions.
2. The Prior Art
Oral malodor, plaque, gingivitis, periodontal disease, and discoloration of the teeth, are all undesirable conditions that affect many people. Malodor of the oral cavity is also known as halitosis or bad breath and it is generally believed that the cause of this condition is due to the presence of anaerobic bacteria, especially gram-negative anaerobic bacteria, in the mouth. These bacteria will generate volatile sulfur compounds (VSC), which are known to cause breath malodor.
Three chemical compounds cause some breath malodor, specifically, hydrogen sulfide (Hxe2x80x94Sxe2x80x94H), methyl mercaptan (CH3xe2x80x94Sxe2x80x94H) and dimethyl sulfide (CH3xe2x80x94Sxe2x80x94CH3). These compounds result from the degradation of epithelial cells and bacteria in the oral cavity. The polypeptide chains of the epithelial cell walls are composed of a series of amino acids including cysteine and methionine, which contain sulfur side chains. The death of microorganisms or epithelial cells results in degradation of the polypeptide chains into their amino acid components, especially cysteine and methionine. Cysteine and methionine are precursors to the formation of VSC.
Oral malodor not only comes from the posterior dorsal surface of the tongue but also from periodontal pockets. A person with gingivitis or periodontal disease may have increased oral malodor from disintegrated epithelial cells. Epithelial cells turn over faster if inflammation is present. Therefore, a larger number of these dead epithelial cells remain in the oral cavity and will degrade into the malodorous compounds. In addition VSC will also alter the epithelial barrier, permitting penetration of the barrier by antigenic substances.
Oral care compositions, such as toothpaste, gels, mouthwashes, mouth rinses, gums, mouth sprays and lozenges, are directed, completely or in part, towards alleviating the conditions in the mouth which cause malodor, generally by physical means, such as brushing teeth with a dentifrice or by chemical means. The effectiveness of oral care compositions is generally perceived as a function of both 1) the ability of the active components of the oral care composition in attacking the conditions which bring about oral malodor, plaque, gingivitis, periodontal disease, and discoloration of the teeth and 2) prolonged smooth lasting effect and long lasting flavor and cooling characteristics in the mouth perceived by the user. Dentifrice manufacturers are constantly seeking ways to prolong the smooth lasting effect and flavor and cooling characteristics of oral care compositions.
Humectants and emollients absorb and promote the retention of moisture from the air. Traditional humectants in oral care compositions are glycerol, sorbitol or glycols. One of the more common humectants used in oral care compositions is glycerol. Glycerol will absorb moisture in the mouth, which serves to diminish the overall smooth lasting effect perceived by the user.
Flavor and cooling effects result primarily from the incorporation of flavoring and cooling agents in the oral care compositions. The objective in increasing the flavoring and cooling effect of an oral care composition is to increase the time that the flavoring and/or cooling agents remain effective after the oral care composition is applied by the consumer. Expensive and cost prohibitive methods of encapsulation are generally the only known means of achieving this objective. A formulation which efficiently enhances the flavoring and cooling effects of oral care compositions without costly means such as encapsulation has long eluded the dentifrice and oral care industry.
Diglycerol has, to the inventor""s knowledge, not been used in oral care compositions as a humectant or emollient, or otherwise. For example, U.S. Pat. No. 4,726,943 describes anti-caries compositions comprising phosphoric acid esters of alkoylated polyols, including diglycerol, as an active component with low molecular weight polyethylene glycols, glycerol and sorbitol as humectants in the composition.
An object of the invention was to develop oral care compositions, such as toothpaste, gels, mouthwashes, mouth rinses, gums, mouth sprays and lozenges, which have an enhanced and/or prolonged smooth lasting effect.
A further object of the invention was to develop oral care compositions that have long lasting flavor and cooling characteristics in the mouth.
Yet another object of the invention was to develop oral care compositions having enhanced prolonged smooth lasting effect and long lasting flavor and cooling characteristics in the mouth without the need for special processing or techniques, such as encapsulation.
These and other objects of the invention are achieved by the incorporation of diglycerol as a humectant and/or emollient in oral care compositions. The diglycerol may be used with other humectants and emollients in the compositions and can replace some or all of the traditional and conventional humectant components of oral care compositions. The oral care compositions comprising diglycerol have enhanced prolonged smooth lasting effect and/or long lasting flavor and cooling effect due in part to the characteristics of the diglycerol molecule and its interaction with flavoring agents, which may incorporate cooling agents, after application of the composition.
In the present Specification, all parts and percentages are on a weight/weight basis unless otherwise specified.
The invention pertains to oral care compositions comprising diglycerol which unexpectedly have an enhanced and/or prolonged smooth lasting effect such as long lasting flavor and cooling characteristics in the mouth. The diglycerol is a humectant and/or emollient in the composition and can be used with other humectants and emollients. The compositions can further comprise other ingredients, additives and fillers.